Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already cover readOnlyHint and destructiveHint, so the safety profile is known. The description adds behavioral context about immutability of versions and the hasMore flag indicating pagination, which are not captured in annotations. It does not contradict annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.